Press

ABSTRACT

A press contains an oscillating doctor and a motor for driving the oscillating doctor axially. The press further has at least one oscillating roller (ink distributor roller and/or damping solution distributor roller) and an oscillating mechanism, via which the oscillating roller is connected to the motor such that the oscillating roller and the oscillating doctor can be driven axially together by the motor.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a press having an oscillating doctorand a motor for driving the oscillating doctor axially.

In published, non-prosecuted German patent application DE 31 17 341 A1(corresponding to U.S. Pat. No. 4,428,291), such a press is describedand it is emphasized that an engraved roller of the press, correspondingto the prior art, would make it unnecessary to roll out the tackyprinting ink to form a thin film, which would permit a simple andspace-saving inking unit construction.

The drawback here is that the excessive simplification of the inkingunit and printing unit construction is made at the cost of printingquality.

2. Summary of the Invention

It is accordingly an object of the invention to provide a press thatovercomes the above-mentioned disadvantages of the prior art devices ofthis general type, in which there is an acceptable compromise betweenthe simplification of the printing unit construction and printingquality.

With the foregoing and other objects in view there is provided, inaccordance with the invention, a press. The press contains anoscillating doctor, a motor for driving the oscillating doctor axially,at least one oscillating roller, and an oscillating mechanism connectingthe oscillating roller to the motor such that the oscillating roller andthe oscillating doctor are driven axially together by the motor.

The press according to the invention has an oscillating doctor and amotor for driving the oscillating doctor axially. The press further hasat least one oscillating roller and an oscillating mechanism, via whichthe oscillating roller is connected to the motor in such a way that theoscillating roller and the oscillating doctor can be driven axiallytogether by the motor.

In the press according to the invention, by the oscillating roller, itis possible not only to roll out the printing ink or the dampingsolution but even to distribute it over the printing width, so that ahigh printing quality is ensured.

Since no separate motor is required to drive the axial back and forthmovement of the oscillating roller and, instead, the motor which ispresent in any case and which drives the axial back and forth movementof the oscillating doctor is also used to drive the axial back and forthmovement of the oscillating roller, the printing unit construction isnot disproportionately complicated by the integration of the oscillatingroller.

In one development, the press contains an anilox inking unit, to whichthe oscillating doctor belongs.

In one further development, the press contains an offset printing unit,to which the anilox inking unit belongs.

In a further development, the anilox inking unit contains an engravedroller having an engraved roller gear and an ink applicator rollerhaving an ink applicator roller gear. The engraved roller gear and theink applicator roller gear are braced against each other under theaction of a load torque in order to secure their tooth flank contact.The oscillating doctor and the oscillating roller are disposedmechanically in such a way that the oscillating doctor and theoscillating roller contribute to the production of the load torque.

In a further development, the oscillating mechanism is assigned a springin order to keep the load torque constant.

In a further development, the spring is disposed mechanically in such away that the spring is always stressed to the maximum when theoscillating doctor or the oscillating roller is in a dead position inthe course of its back and forth movement.

In a further development, the spring is assigned a cam in order tostress the spring periodically.

In a further development, the engraved roller and the ink applicatorroller are in rolling contact with each other without any bearer ring.

In a further development, the oscillating doctor bears on the engravedroller.

In a further development, the oscillating mechanism is configured insuch a way that the oscillating doctor and the oscillating rolleroscillate axially with oscillation amplitudes that are different fromeach other.

In a further development, the oscillating mechanism is configured insuch a way that the oscillating doctor and the oscillating rolleroscillate with an oscillation phase offset in relation to each other.

In a further development, the oscillating doctor and the oscillatingroller are connected mechanically in parallel with each other via theoscillating mechanism.

In a further development, the oscillating doctor and the oscillatingroller are connected mechanically in series with each other via theoscillating mechanism.

In a further development, the oscillating roller is an ink distributorroller.

In a further development, the oscillating roller is a damping solutiondistributor roll.

Other features which are considered as characteristic for the inventionare set forth in the appended claims.

Although the invention is illustrated and described herein as embodiedin a press, it is nevertheless not intended to be limited to the detailsshown, since various modifications and structural changes may be madetherein without departing from the spirit of the invention and withinthe scope and range of equivalents of the claims.

The construction and method of operation of the invention, however,together with additional objects and advantages thereof will be bestunderstood from the following description of specific embodiments whenread in connection with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagrammatic illustration of a first exemplary embodiment,in which an oscillating doctor, an ink distributor roller and a dampingsolution distributor roller are connected mechanically in parallel withone other via an oscillating shaft of the oscillating mechanismaccording to the invention;

FIG. 2 is a diagrammatic illustration of a second exemplary embodiment,in which the oscillating doctor and the damping solution distributorroller are connected mechanically in parallel with each other via acrank belonging to the oscillating mechanism;

FIG. 3 is a diagrammatic illustration of a third exemplary embodiment,in which the oscillating doctor and the damping solution distributorroller are connected mechanically in series by couplers belonging to theoscillating mechanism;

FIGS. 4 and 6 are diagrammatic illustrations of common details of theexemplary embodiments illustrated in FIGS. 1 to 3; and

FIG. 5 is a diagrammatic, perspective view of the oscillating shaft ofthe first exemplary embodiment in a three-dimensional illustration.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

In all the figures of the drawing, sub-features and integral parts thatcorrespond to one another bear the same reference symbol in each case.Referring now to the figures of the drawing in detail and first,particularly, to FIGS. 1-3 thereof, there is shown a press 1 having anoffset printing unit 2, which contains a printing form cylinder 3, ablanket cylinder 4 and an impression cylinder 5. The offset printingunit 2 further contains an anilox inking unit 6 having an engravedroller 7 and an ink applicator roller 8, and also a dampening unit 11having a dip roller 12, a metering roller 13, a damping solutionapplicator roller 14 and a damping solution distributor roller 15 as anoscillating roller. The anilox inking unit 6 contains an oscillatingdoctor 10, which bears on the engraved roller 7 and feeds the highlyviscous printing ink to the latter. The oscillating doctor 10 is ametering doctor different from a cleaning doctor and is, for example, achamber-type doctor. The axial back and forth movement of theoscillating doctor 10 is driven via an oscillating mechanism 16, whoseconstruction, which is partly different from exemplary embodiment toexemplary embodiment, will be explained in detail in the following text.

FIGS. 1 and 5 show a first exemplary embodiment, in which an inkdistributor roller 9 bears on the engraved roller 7 as an oscillatingroller. The two oscillating rollers, that is the ink distributor roller9 and the damping solution distributor roller 15, and the oscillatingdoctor 10 are connected to one another via the oscillating mechanism 16in such a way that these three aforementioned oscillating elements canbe driven axially together by one and the same motor, a main motor 55 ofthe press 1, illustrated only schematically in the drawing. The driveoutput from the main motor 55 is transmitted from a blanket cylindergear 17 via a printing form cylinder gear 18, an ink applicator rollergear 19, an engraved roller gear 20, a drive gear 21 belonging to theoscillating mechanism 16, a worm gear mechanism 22 and a first couplermechanism 23 to an oscillating shaft 27, in the above-mentioned order.

The drive gear 21 meshes with the engraved roller gear 20 and theprinting form cylinder gear 18 meshes with the ink applicator rollergear 19, so that the engraved roller gear 20 and the ink applicatorroller gear 19 are braced against each other under the drive torqueexerted on the ink applicator roller gear 19 by the printing formcylinder gear 18 and the opposing load torque of the oscillatingmechanism 16, which load torque is exerted by the oscillating mechanism16 on the engraved roller gear 20 via the drive gear 21. This bracingsecures the tooth flank contact, important for the printing quality,between the engraved roller gear 20 and the ink applicator roller gear19 and would not be provided to a sufficient extent if the oscillatingmechanism 16 were driven directly from the printing form cylinder 3 andnot via the anilox inking unit 6 or its rollers, that is to say if thedrive gear 21 were to mesh with the printing form cylinder gear 18.

In the last-named, hypothetical case, the two oscillating rollers andthe oscillating doctor 10 would contribute nothing to the torque, sothat the latter would have to be produced by the engraved roller 7 onits own and, accordingly, the bracing of the toothing systems would betoo small. By contrast, in the first exemplary embodiment shown, thetoothing system bracing is even so high that rolling contact withoutbearer rings is made possible between the engraved roller 7 and the inkapplicator roller 8. The engraved roller 7 and the ink applicator roller8 do not need to be equipped with supporting rings running on oneanother, which in principle act like bearer rings, in order to ensurethe printing quality, which not only results in that the productioncosts are reduced but also the roller adjustment is simplified.

The worm gear mechanism 22 contains a worm gear 28 and a worm 29, whichis fixed to the drive gear 21 so as to rotate with it via a connectingshaft 30. A first coupler mechanism 23 contains a circulating drivecrank, a rocker moving to and fro as an output drive and a crank rod 32connecting the drive crank in an articulated manner to the rocker, andthus corresponds to the “oscillating rocker” mechanism type. The drivecrank is formed by the worm gear 28 and the rocker by a long lever arm31 belonging to the oscillating shaft 27. The oscillating shaft 27executes a rotary swinging motion 33 with a change of direction, duringwhich the long lever arm oscillates back and forth, and transmits thedrive output via a second coupler mechanism 24 to the oscillating doctor10, via a third coupler mechanism 25 to the ink distributor roller 9 andvia a fourth coupler mechanism 26 to the damping solution distributorroller 14. The second 24, third 25 and fourth 26 coupler mechanisms eachcontain as a swinging drive arm a short lever arm 34 belonging to theoscillating shaft 27, a rocker 35 as output dive and a coupler 36 inorder to connect the short lever arm 34 in an articulated manner to therocker 35, and thus corresponds to the “double rocker” mechanism type.

FIG. 1 shows that the oscillating doctor 10, the ink distributor roller9 and the damping solution distributor roller 14 are connectedmechanically in parallel with one another via the oscillating mechanism16, more precisely via its second 24, third 25 and fourth 26 couplermechanisms. By corresponding dimensioning of the mechanism elements ofthe oscillating mechanism 16, the latter is configured in such a waythat it swings the oscillating doctor 10 axially with a different,preferably smaller, amplitude than the oscillating rollers (inkdistributor roller 9, damping solution distributor roller 14). Forexample, the amplitude of the oscillating doctor 10 can be about 1millimeter and the amplitude of the distributor and oscillating rollers9, 14 can be about 5 millimeters, therefore a multiple.

FIG. 2 shows a second exemplary embodiment that does not differ from thefirst with respect to the gears 17 to 20. In the second exemplaryembodiment, the oscillating mechanism 16 contains a pinion 37, which isconnected to the ink applicator roller gear 19 so as to rotate with itand meshes with a gear which forms a common crank 38 for a first crankrod 39 and a second crank rod 40. The first crank rod 39 is connected tothe oscillating doctor 10 via one rocker 35, and the second crank rod 40is connected via the other rocker 35 to the damping solution distributorroller 15, which is the only oscillating roller in the second exemplaryembodiment.

The two oscillating elements, that is the distributor or oscillatingroller 15 and the oscillating doctor 10, are therefore connectedmechanically in parallel with each other via the oscillating mechanism16 or its two coupler mechanisms of the “oscillating rocker” mechanismtype, so that these oscillating elements can be driven axially togetherby the aforesaid main motor 55. By corresponding dimensioning of themechanism elements of the oscillating mechanism 16, the latter isconfigured in such a way that, between the axial oscillation of theoscillating doctor 10 and the axial oscillation of the distributor oroscillating roller 15, a phase shift is provided, such that oscillatingmovements of these two oscillating elements which are opposite to eachother, at least from time to time, are established. Furthermore, thedimensioning ensures that in each case, for each two revolutions of theprinting form cylinder 3, both the oscillating doctor 10 and thedistributor or oscillating roller 15 execute a complete axialoscillation; the oscillating movements thus have a half-turn nature.

FIG. 3 shows a third exemplary embodiment which does not differ from thesecond exemplary embodiment with respect to the section of the mechanismtransmitting the drive output from the pinion 37 to the oscillatingroller (damping solution distributor roller 15). In the third exemplaryembodiment, provision is likewise made for the common motor or mainmotor 55 to drive the two oscillating elements (oscillating doctor 10,distributor or oscillating roller 15) axially together.

The special feature of the third exemplary embodiment is that the twooscillating elements are connected mechanically in series with eachother via the oscillating mechanism 16, so that the drive output istransmitted first via the coupler mechanism containing the crank rod 40to the one oscillating element, here the distributor or oscillatingroller 15, and then passed on from this oscillating element via afurther coupler mechanism to the other oscillating element, here theoscillating doctor 10. The further coupler mechanism corresponds to the“double rocker” mechanism type and contains a coupler 4 which isconnected mechanically to the oscillating elements via a rocker 35.

According to a modification of the third exemplary embodiment, notillustrated in the drawing, the coupler 41 and the rockers 35 arereplaced by a single rocker in order to form the section of themechanism connecting the two oscillating elements.

FIG. 4 shows that an oscillating element 42 is mounted in a side frame43 such that it can be displaced axially. This oscillating element 42can be the ink distributor roller 9 of the first exemplary embodiment orthe damping solution distributor roller 15 or the oscillating doctor 10of the first to third exemplary embodiment. It becomes clear that therocker 35 contains an axis of rotation 44, a first lever arm 45 and asecond lever arm 46. A mechanism element 54 is attached to the firstlever arm 45 and the second lever arm 46 has a driver roller 47, bywhich the second lever arm 46 engages in an annular groove 48, which hasan axle journal 49 of the oscillating element 42.

If, for example, the oscillating element 42 is the oscillating doctor 10of the second exemplary embodiment (see FIG. 2), then the mechanismelement 54 is the first crank rod 39.

FIG. 6 shows a cam mechanism integrated in the oscillating mechanism 16and having a cam 50 and a cam roller 51 which is pressed against the cam50 by a spring 52. The cam 50 is connected to a crank 53 so as to rotatewith it, which can be the worm gear 28 of the first exemplary embodimentor the crank 38 of the second and third exemplary embodiment. The spring52 is periodically stressed by the cam 50 rotating together with thecrank 53 in such a way that the spring 52 reaches its maximum stress ineach case at a time at which at least one of the oscillating elements islocated at the point of reversal or the dead position of its oscillatingmovement.

The oscillating element, which is axially stationary at this time,contributes nothing to the production of the aforesaid load torque whichsecures the tooth flank bracing present between the engraved roller gear20 and the ink applicator roller gear 19.

The cam contour of the cam 50 is such that the failure of the loadtorque induced by the dead position is compensated for by the stress ofthe spring 52 and the load torque is kept continuously constant.

This application claims the priority, under 35 U.S.C. § 119, of Germanpatent application No. 10 2004 037 765.0, filed Aug. 4, 2004; the entiredisclosure of the prior application is herewith incorporated byreference.

1. A press, comprising: an oscillating doctor; a motor for driving saidoscillating doctor axially; at least one oscillating roller; and anoscillating mechanism connecting said oscillating roller to said motorsuch that said oscillating roller and said oscillating doctor are drivenaxially together by said motor.
 2. The press according to claim 1,further comprising an anilox inking unit containing said oscillatingdoctor.
 3. The press according to claim 2, further comprising an offsetprinting unit containing said anilox inking unit.
 4. The press accordingto claim 3, wherein said anilox inking unit further contains: anengraved roller having an engraved roller gear; and an ink applicatorroller having an ink applicator roller gear, said engraved roller gearand said ink applicator roller gear are braced against each other underan action of a load torque for securing their tooth flank contact, andsaid oscillating doctor and said oscillating roller are disposedmechanically such that said oscillating doctor and said oscillatingroller contribute to producing the load torque.
 5. The press accordingto claim 4, wherein said oscillating mechanism has a spring for keepingthe load torque constant.
 6. The press according to claim 5, whereinsaid spring is disposed mechanically such that said spring is alwaysstressed to a maximum when said oscillating doctor or said oscillatingroller is in a dead position in a course of its back and forth movement.7. The press according to claim 6, wherein said oscillating mechanismhas a cam for stressing said spring periodically.
 8. The press accordingto claim 4, wherein said engraved roller and said ink applicator rollerare in rolling contact with each other without any bearer ring.
 9. Thepress according to claim 4, wherein said oscillating doctor bears onsaid engraved roller.
 10. The press according to claim 1, wherein saidoscillating mechanism is configured such that said oscillating doctorand said oscillating roller oscillate axially with oscillationamplitudes that are different from each other.
 11. The press accordingto claim 1, wherein said oscillating mechanism is configured such thatsaid oscillating doctor and said oscillating roller oscillate with anoscillation phase offset in relation to each other.
 12. The pressaccording to claim 1, wherein said oscillating doctor and saidoscillating roller are connected mechanically in parallel with eachother via said oscillating mechanism.
 13. The press according to claim1, wherein said oscillating doctor and said oscillating roller areconnected mechanically in series with each other via said oscillatingmechanism.
 14. The press according to claim 1, wherein said oscillatingroller is an ink distributor roller.
 15. The press according to claim 1,wherein said oscillating roller is a damping solution distributorroller.